1. Field of the Invention
The present invention provides nucleotide sequences from Coryneform bacteria which code for the ccpA1 gene and a process for the fermentative preparation of amino acids, in particular L-lysine, by attenuation of the ccpA1 gene. The ccpA1 gene codes for the ccpA1 protein, which is a catabolite control protein A.
2. Description of the Background
L-Amino acids, in particular L-lysine, are widely used, for example in human medicine, in the pharmaceuticals industry, in the foodstuffs industry and, very particularly, in animal nutrition.
It is known that amino acids may be prepared by fermentation from strains of Coryneform bacteria, in particular, Corynebacterium glutamicum. Due to the importance of L-amino acids, efforts are constantly made to improve preparatory processes therefor. Improvements can relate to fermentation measures, such as, for example, stirring and supply of oxygen, or the composition of the nutrient media, such as, for example, sugar concentration during the fermentation, or product work up by, for example, ion exchange chromatography, or the intrinsic output properties of the microorganism itself.
Methods of mutagenesis, selection and mutant selection are used to improve the output properties of these microorganisms. Strains which are resistant to antimetabolites or which are auxotrophic for metabolites of regulatory importance and which produce amino acids are obtained in this manner.
Methods using recombinant DNA techniques have also been employed for some years for improving Corynebacterium strains which produce L-amino acid. However, a need still exists for improved fermentation procedures for preparing amino acids, in particular L-lysine.